148 PROCEEDINGS OF THE ROYAL SOCIETY OF QUEENSLAND. 



material, (juartz, and secondary minerals, resulting from 

 the alteration of the felspars. Small patches of liinonite 

 are scattered throughout the rock. The felspar pheno- 

 crysts, which vary from 2-7 mm. in length, occur in very 

 altered crystals, and are really pseudomorphous aggregates 

 of muscovite and other secondary minerals. In spite of 

 this the felspars still show idiomorphic outlines, and zon- 

 ing is still recognisable (indeed the zoning is apparent in 

 the hand specimen), and points to the felspars as Plagio- 

 clases, although no more exact determination is possible. 

 In some cases these phenocrysts partly enclose chloritic 

 clusters, which are secondary after some ferro-magnesian 

 mineral. Quartz occurs as a few phenocrysts up to 2 mm. 

 in diameter, which are very similar to those described iu 

 {D.7). The ferro-magnesian constituents are represented 

 by patches of chloritic material. 



Name. — Quartz Porphyry (Granodiorite Porphyry). 



IV. COMPARISON WITH ROCKS OF OTHER AREAS. 



{a) New England and Stanthorpe — 



In Part I. of this paper the author pointed out that the 

 granitic and allied rocks of the Enoggera district were 

 closely comparable with those of New" England in northern 

 New South Wales, and the contiguous masses of the 

 Stanthorpe district in the southern part of Queensland. 

 The age of these great intrusions was seen to be much about 

 the same, i.e., very late Palaeozoic ; structurally they 

 followed the same trends, while mineralogically they were 

 very similar. 



Even more striking resemblances ar*- discovered if the 

 sequence of events in the different areas be compared. 

 Table II. has been drawn up for this purpose. The order . 

 of intrusion in the New England district is that found by 

 Andrews, while in the adjacent Stanthorpe area the 

 sequence adopted is that of Saint-Smith. These two areas 

 are practically continuous, so that they can be very 

 definitely correlated. If these two columns be compared it 

 will be found that, although the grouping and naming differ 

 somewhat, the rock types and their order of intrusion are 

 identical, with but one exception. The "Sphene" granite 

 is considered by Andrews to be definitely earlier than the 



